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xiumin07032k
2 năm trước
Một bếp điện khi hoạt động bình thường có điện trở R = 80 ôm và cường độ dòng điện i = 2,5A. a. Tính nhiệt lượng mà bếp điện toả ra trong 1s. b. Dùng bếp điện trên để đun sôi 1,5L nước có nhiệt độ ban đầu là 25°C thì thời gian đun nước là 20 phút. Coi rằng nhiệt lượng cũng cấp để đun sôi nước là có ích, tính hiệu suất của bếp. Cho biết nhiệt dung riêng của nước là c = 4200 J/Kg.K c. Tính điện năng mà bếp sử dụng trong 1 giờ ? Giúp mik với, mik đang cần gấp. Vote 5 sao cho những bạn giúp mik, mik cảm ơn.
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